COVID-19 as an occupational disease.

The impact of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 permeates all aspects of society worldwide. Initial medical reports and media coverage have increased awareness of the risk imposed on healthcare workers in particular, during this pandemic. However, the health implications of COVID-19 for the global workforce are multifaceted and complex, warranting careful reflection and consideration to mitigate the adverse effects on workers worldwide. Accordingly, our review offers a framework for considering this topic, highlighting key issues, with the aim to prompt and inform action, including research, to minimize the occupational hazards imposed by this ongoing challenge. We address respiratory disease as a primary concern, while recognizing the multisystem spectrum of COVID-19-related disease and how clinical aspects are interwoven with broader socioeconomic forces.

Trends in Occupations and Work Sectors Among Patients With Work-Related Asthma at a Canadian Tertiary Care Clinic.

BACKGROUND: Work-related asthma (WRA) is the most common chronic occupational lung disease in the developed world. Several factors including sociodemographic status and occupation/industry increase the risks of developing WRA. In this study, we sought to identify changes in patterns and characteristics among patients with WRA over a 15-year period in an occupational lung disease clinic. METHODS: We performed a retrospective analysis of patients with WRA charts at the Occupational Lung Disease Clinic of a University Hospital in Toronto, Canada. Patients were divided into two periods classified by first attendance at the clinic 2000 through 2007 and 2008 through 2015. Comparisons between the two periods included: sociodemographic characteristics, smoking status, occupations, exposures, and submitted workers' compensation claims. RESULTS: Fewer occupational asthma cases were seen in the more recent period vs the earlier period (40 vs 74 cases), with a smaller reduction in work-exacerbated asthma cases (40 vs 58). The recent period included a significantly smaller proportion employed in the manufacturing industry and isocyanate-induced cases compared with the earlier period. An increased proportion were employed in health-care and education industries (primarily cleaners and teachers) in the recent period, consistent with a corresponding increased frequency of cleaning agents and dust exposures. CONCLUSIONS: The changes observed in work sectors in the patients with WRA in this clinic in Toronto are consistent with reductions reported in Ontario workers' compensation claims for occupational asthma and may relate to preventive measures. Cleaners and teachers should be a focus of further intervention measures for work-related asthma.

Evaluation of Occupational and Environmental Factors in the Assessment of Chronic Cough in Adults: A Systematic Review.

BACKGROUND: Several recent cough guidelines have advised consideration of occupational or environmental causes for chronic cough, but it is unclear how frequently this recommendation has been routinely applied. Therefore, we undertook a systematic review to address this aspect. METHODS: Cough guidelines and protocols were reviewed to identify recommendations for assessment of occupational and environmental aspects of chronic cough. The systematic search previously used to identify intervention fidelity to the use of protocols for diagnosis and management of chronic cough in adults was used for this review after extension to June 2015. PubMed, Scopus, and the Cochrane Library were searched using the same search terms and inclusion criteria as previously. Papers that met our criteria were then reviewed to identify methods used to assess occupational and environmental aspects of chronic cough and the outcomes of these assessments. RESULTS: Among the 10 general chronic cough guidelines and protocols identified, only the three published since 2006 included details advising detailed occupational and environmental assessments. One additional cough statement focused entirely on occupational cough. Of the 28 cohort studies of patients with chronic cough that specifically noted that they followed guidelines or protocols, none provided details of occupational and environmental assessments. CONCLUSIONS: Despite published recommendations, it is not apparent that occupational and environmental causes for chronic cough are addressed in detail during assessments of patients with chronic cough. This leaves open to speculation whether lack of recognition of an occupational cause may delay important preventive measures, put additional workers at risk, and/or be the reason why a chronic cough may remain unexplained.

Longitudinal assessment of lung function decline in the occupational setting.

PURPOSE OF REVIEW: Spirometry is performed in the work setting as part of medical surveillance of workers with potentially respiratory hazardous work exposures, to identify early disease and evaluate the effectiveness of preventive interventions. However, many clinicians are not familiar with workplace medical surveillance and how to evaluate longitudinal spirometry over time. RECENT FINDINGS: A recent American Thoracic Society technical standards report addressed issues related to performing spirometry in the work setting, including the interpretation of longitudinal lung function. Important considerations in assessing longitudinal lung function are reviewed. Recent studies evaluating the impact of selected occupational exposures on longitudinal lung function are reviewed. SUMMARY: Recent longitudinal studies of exposed workers have identified novel occupational respiratory diseases such as flavoring-related lung disease, and advanced our understanding of more familiar exposures such as mineral dusts. Clinicians will increasingly need to be able to evaluate longitudinal spirometry, including thresholds that trigger further evaluation.

Diisocyanate and non-diisocyanate sensitizer-induced occupational asthma frequency during 2003 to 2007 in Ontario, Canada.

OBJECTIVE: To investigate proportions and outcomes of isocyanate and other causes of occupational asthma (OA) claims in Ontario, Canada, 2003 to 2007. METHODS: New accepted workers' compensation claims for OA compensated by the Ontario Workplace Safety and Insurance Board were retrospectively reviewed. RESULTS: There were 112 allowed claims for OA-30 (26.8%) from diisocyanates (ISO) and 82 (73.2%) from other causes (non-diisocyanates [N-ISO]). The most common occupations for ISO OA were production workers (50%). The most common agents in the N-ISO group were flour (13%) and metal dusts/fumes (10%). At a median time of 8 months postdiagnosis, 55% of ISO and 56.4% of N-ISO workers, respectively, were unemployed. CONCLUSIONS: Diisocyanates OA compensation claims in Ontario are recognized at a lower absolute number and proportion of all OA claims than those in earlier periods. More than half from all causes were unemployed at a median of 8 months postdiagnosis.

An official American Thoracic Society proceedings: work-related asthma and airway diseases. Presentations and discussion from the Fourth Jack Pepys Workshop on Asthma in the Workplace.

Work-related asthma is a common occupational lung disease. The scope of the Fourth Jack Pepys Workshop that was held in May 2010 went beyond asthma to include discussion of other occupational airway diseases, in particular occupationally related chronic obstructive pulmonary disease (COPD) and bronchiolitis. Aspects explored included public health considerations, environmental aspects, outcome after diagnosis, prevention and surveillance, and other work-related obstructive airway diseases. Consistent methods are needed to accurately estimate the comparative burden of occupation-related airway diseases among different countries. Challenges to accomplishing this include variability in health care delivery, compensation systems, cultural contexts, and social structures. These factors can affect disease estimates, while heterogeneity in occupations and workplace exposures can affect the underlying true prevalence of morbidity. Consideration of the working environment included discussion of practical methods of limiting exposure to respiratory sensitizers, methods to predict new sensitizers before introduction into workplaces, the role of legislated exposure limits, and models to estimate relative validity of various ameliorative measures when complete avoidance of the sensitizer is not feasible. Other strategies discussed included medical surveillance measures and education, especially for young individuals with asthma and new workers about to enter the workforce. Medical outcomes after development of sensitizer-induced occupational asthma are best following earlier diagnosis and removal from further exposure, but a subset may be able to continue working safely provided that exposure is reduced under close follow-up monitoring. It was recognized that occupationally related COPD is common but underappreciated, deserving further study and prevention efforts.

Impact of a cleaners' strike on compensation claims for asthma among teachers in Ontario.

BACKGROUND: A review of Workplace Safety and Insurance Board (WSIB) claims in Ontario from 1998 to 2002 showed an unusual spike in the number of claims accepted for work-exacerbated asthma (WEA) in April 2001. OBJECTIVE: To identify the cause for the spike in the number of WSIB claims for WEA in April 2001. METHODS: File reviews were performed to identify the occupations of workers with claims accepted for WEA in April 2001 compared with claims during March and May 2001, and during the same months in 2000 and 2002. RESULTS: In April 2001, there were 61 accepted WEA claims; the most common occupation was 'teacher'. In contrast, among educational workers, there was only one WEA claim in the previous month and one in the following month. From March to May in the preceding and following years, there were only four and two claims, respectively. The most frequently implicated causative agents were dust and dirt exposure, which were responsible for 98% of claims; the mean (± SD) number of lost workdays was 6.5±10. The only identified environmental change associated with this spike was a cleaners' strike at all elementary and high schools in the Toronto District School Board in Ontario, which started on March 31, 2001 and ended on May 1, 2001. CONCLUSION: [corrected] The spike in accepted WEA claims in Ontario in April 2001 was temporally associated with a strike by Toronto District School Board cleaners, suggesting acute symptomatic effects of poor workplace (school) maintenance on asthmatic employees. The WSIB database was sufficiently sensitive to capture this phenomenon.

Work-related asthma: a case-based approach to management.

The management of work-related asthma has some differences from management of other asthma. Components of management include not only making as accurate a diagnosis as possible, identifying the causative agent or triggers at work, and managing the asthma with pharmacologic treatment as for other patients with asthma, but also advising on the appropriate work changes that may be needed, assisting the worker with appropriate compensation claims, and supporting protective measures for coworkers. This article discusses the approaches that may be taken for patients with different forms of work-related asthma.

Reduction in diisocyanate and non-diisocyanate sensitizer-induced occupational asthma in Ontario.

OBJECTIVE: To investigate relative frequency and features of diisocyanate (ISO) and non-diisocyanate (N-ISO) allowed occupational asthma (OA) claims in Ontario, Canada, during a 5-year period (1998 to 2002). METHODS: Records were abstracted from the Ontario Workplace Safety and Insurance Board using methodology similar to our previous investigation that had identified 30 ISO and 30 N-ISO claims/yr during 1980 to 1993. RESULTS: There were 99 OA claims: 37 ISO (7.4 claims/yr) and 62 N-ISO (12.4 claims/yr). The ISO group had more males (86% vs 69%, p = 0.01), but there were no other significant differences. The commonest professions were spray painters (41%) and production workers (38%) in the ISO group and production workers (49%) and health care workers (8%) in the N-ISO group. CONCLUSIONS: ISO and N-ISO claims declined from the previous period, especially for ISO, perhaps because of effective surveillance programs.

Work-related asthma in health care in Ontario.

BACKGROUND: The health of workers in health care has been neglected in the past. There are few reports regarding occupational asthma (OA) in this group, and work-exacerbated asthma (WEA) has rarely been considered. METHODS: We examined the frequency of claims for OA and WEA allowed by the compensation board in Ontario, Canada for which industry was coded as "health care" between 1998 and 2002, to determine the frequency of OA and WEA, causative agents, and occupations. RESULTS: During this period, five claims were allowed for sensitizer OA, two for natural rubber latex (NRL), and three for glutaraldehyde/photographic chemicals. The two NRL cases occurred in nurses who had worked for >10 years prior to "date of accident." There were 115 allowed claims for WEA; health care was the most frequent industry for WEA. Compared to the rest of the province, claims in health care made up a significantly greater proportion of WEA claims (17.8%) than OA (5.1%) (odds ratio, 4.1, 95% CI 1.6-11.6; P = 0.002). The rate of WEA claims was 2.1 times greater than that in the rest of the workforce (P < 0.0001). WEA claims occurred in many jobs (e.g., clerk), other than "classic" health care jobs such as nurses, and were attributed to a variety of agents such as construction dust, secondhand smoke, and paint fumes. CONCLUSIONS: WEA occurs frequently in this industrial sector. Those affected and attributed agents include many not typically expected in health care. The incidence of OA claims in this sector in general was low; the continued low number of OA claims due to NRL is consistent with the successful interventions for prevention.

Prevention of occupational asthma.

Prevention of occupational asthma related to a work-sensitizing agent ideally would be achieved by avoidance of exposures that cause immunologic sensitization and subsequent asthma. There are a few examples in which a sensitizing agent has been removed from a work process and others in which exposure has been significantly changed or reduced with associated reduced rates of sensitization and disease. Additional measures include containment, use of robots, ventilation measures, exposure monitoring, and use of respiratory protective devices. Secondary prevention includes medical surveillance, which may involve periodic respiratory questionnaires, spirometry, and immunologic tests aiming to detect sensitization or disease early to allow intervention and improve outcomes. Education measures for workers to understand the meaning of work-related respiratory symptoms and appropriate workplace safety measures have not been formally evaluated but may also be expected to enhance protective measures and lead to earlier diagnosis. Tertiary prevention includes medical management and workers' compensation.

Cost-effectiveness of various diagnostic approaches for occupational asthma.

BACKGROUND: Diagnosis of occupational asthma (OA) by specific inhalation challenge (SIC) can be costly and is not always available. The use of sputum testing to avoid this in some patients may be a more cost-effective alternative. OBJECTIVES: To compare the cost-effectiveness of SIC with serial measurements of sputum cell counts (sputum testing) and peak expiratory flow (PEF) monitoring. METHODS: Clinical data and testing costs for OA in 49 patients were collected during a previously published trial, modelled and compared using TreeAge Pro. Clinical outcome was the percentage of accurately diagnosed patients, using SIC as the gold standard. The PEF approach used the most accurate assessment of five experts who were blinded to SIC results. Differences in the proportion of eosinophils during periods on and off work were used for the sputum testing approach and in PEF/sputum for the combined approach. Unit costs were estimated from charges in Canadian hospitals. Data were analyzed by one-way and two-way analyses, and by probabilistic sensitivity analysis using a Monte Carlo simulation technique. RESULTS: The PEF approach had an estimated accuracy of 52% and cost $365 per patient tested. Compared with PEF monitoring, sputum testing was more accurate and cost an estimated $255 for each additional OA patient correctly diagnosed. SIC costs per additional correct diagnosis were $11,032 compared with sputum testing and $6,458 compared with PEF monitoring. The combined PEF/sputum testing approach was not cost-effective in the base case analysis, but cannot be excluded according to probabilistic sensitivity analyses. CONCLUSIONS: Although SIC remains the reference test to diagnose OA, when this test is not available, sputum testing is a cost-effective alternative to PEF for diagnosis of OA.

Prevention of occupational asthma in Ontario.

Occupational asthma continues to be one of the most common occupational lung diseases in industrialized areas. Primary and secondary preventive measures have been well described, but there are relatively few studies to support the effectiveness of such measures, although the benefits of tertiary measures such as early recognition and removal from further exposure to a causative sensitizing agent are well recognized. In Ontario, a combined approach of preventive measures has shown effectiveness in allergy and asthma from occupational exposure to natural rubber latex. In addition, a program to reduce exposure to diisocyanates and introduce medical surveillance was associated with earlier diagnosis and fewer cases in a compensation population. However there remain barriers to the early diagnosis of occupational asthma in Ontario, especially in workers of lower education and lower income. In addition, there is recognized need for further physician education to allow early suspicion and diagnosis of occupational asthma.